let I be non empty set ; for H being Group-like associative multMagma-Family of I
for s being Element of (FreeProduct H)
for k being Nat st 1 <= k & k <= len (factorization s) holds
ex i being Element of I ex g being Element of (H . i) st (factorization s) . k = [*i,g*]
let H be Group-like associative multMagma-Family of I; for s being Element of (FreeProduct H)
for k being Nat st 1 <= k & k <= len (factorization s) holds
ex i being Element of I ex g being Element of (H . i) st (factorization s) . k = [*i,g*]
let s be Element of (FreeProduct H); for k being Nat st 1 <= k & k <= len (factorization s) holds
ex i being Element of I ex g being Element of (H . i) st (factorization s) . k = [*i,g*]
let k be Nat; ( 1 <= k & k <= len (factorization s) implies ex i being Element of I ex g being Element of (H . i) st (factorization s) . k = [*i,g*] )
set F = uncurry (injection H);
assume
( 1 <= k & k <= len (factorization s) )
; ex i being Element of I ex g being Element of (H . i) st (factorization s) . k = [*i,g*]
then A1:
k in dom (factorization s)
by FINSEQ_3:25;
then
k in dom (nf s)
by FUNCT_1:11;
then A2:
(nf s) . k in rng (nf s)
by FUNCT_1:3;
then consider x, y being object such that
A3:
(nf s) . k = [x,y]
by RELAT_1:def 1;
x in dom H
by A2, A3, Th7;
then reconsider i = x as Element of I ;
reconsider g = y as Element of (H . i) by A2, A3, Th9;
take
i
; ex g being Element of (H . i) st (factorization s) . k = [*i,g*]
take
g
; (factorization s) . k = [*i,g*]
thus (factorization s) . k =
(uncurry (injection H)) . ((nf s) . k)
by A1, FUNCT_1:12
.=
[*i,g*]
by A3, Lm6
; verum